# Photon in a Box

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It isn't actually mass, even though mass and energy are related. - the claim, no reasoning here.

In physics jargon, the mass of an object is called its 'invariant mass,' and the photon has no invariant mass. - the claim, no reasoning here.

It comes out of the equations, because you can't transform yourself into the photon's frame. An object traveling at c can't have a rest mass. The equations diverge. The momentum is E/c, and this relationship matches up quite well with experiment.

There are other instances of experimental data that support the zero rest mass:

"It is almost certainly impossible to do any experiment that would establish the photon rest mass to be exactly zero. The best we can hope to do is place limits on it. A non-zero rest mass would introduce a small damping factor in the inverse square Coulomb law of electrostatic forces. That means the electrostatic force would be weaker over very large distances.

Likewise, the behavior of static magnetic fields would be modified. An upper limit to the photon mass can be inferred through satellite measurements of planetary magnetic fields. The Charge Composition Explorer spacecraft was used to derive an upper limit of 6 × 10-16 eV with high certainty. This was slightly improved in 1998 by Roderic Lakes in a laboratory experiment that looked for anomalous forces on a Cavendish balance. The new limit is 7 × 10-17 eV. Studies of galactic magnetic fields suggest a much better limit of less than 3 × 10-27 eV, but there is some doubt about the validity of this method."

There are a couple of references listed on that page. More, presumably, if you care to Google.

You guys are believing in your textbooks so much, you're not even able to distinguish between claim (tautology) and reasoning (induction). You're just a new sort of believers of modern era, who only have switched the Bibles. And this is just bad and sad.

Your demonstrated knowledge here begins and ends with E=mc^2, and you have the temerity to write this?

I'm reminded of the line from the movie "Arthur."

"I really wouldn't know, sir. I'm just a servant. On the other hand, go screw yourself."

I mean, seriously. Do you expect any kind of reasonable exchange if you spout this kind of fallacy-ridden appeal to conspiracy, "it's a religion" strawman crap? Your request for justification of standard equations implies you've never even picked up a textbook on this. And yet you come here saying "it's all wrong," but you haven't made the effort to find out what you're arguing against.

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...it comes out of the equations, because you can't transform yourself into the photon's frame....

This simply means, we would never be able to measure the mass of photon directly. Which effectivelly means, when weighting some photon, we will be always forced to weight some other system (like the photon resonator), as you pointed out correctly above. And I've nothing against such stance.

But the fact, we cannot never measure the photon mass directly effectivelly means, you cannot never prove, the photon has no rest mass at the same time. Therefore your argument can be interpreted by symmetric way.

The true is, the formally thinking people have trouble with concept of mass of photon, because it will make their simple equations singular. But this is just a problem of formal math, not the reality, which gets into singularities quite often.

...There are other instances of experimental data that support the zero rest mass....

As I explained above, every localised object is required to have rest mass due the non-zero space-time curvature, which defines the shape of such particle. If we apply this on the photon rest mass problem, we can decide, the only photon, which can stay reliably at rest is the photon, whose diameter is comparable with diameter of observable universe, so it cannot move inside it. The effective energy of such photon corresponds the rest mass of photon after then. Such rest mass is incredibly tiny (bellow 10E-50 kg), but it's definitelly non zero, because the observable Universe isn't of infinite diameter due the limited speed of light and the age of observable Universe generation.

Such approach violates no direct photon rest mass measurement, simply because of limited sensitivity of experiments. It just puts a lower limit for the photon rest mass. If we prove later, the Universe is older, then the estimation of rest mass of photon will decrease correspondingly.

... "it's a religion" strawman crap?....

I'm just describing exactly, what I can see. No less, no more. And this is not about some conspiracy at all. The people like you are speaking for himself by the same way, like me. Neverthelles, the intersubjective thinking affects the thinking of individuals by tangible way - the human society is a sort of colony, a metarorganism. The community stance affects the behavior of individuals subconsciously.

At the moment, you cannot justify your stance, or even delete my posts without reasoning, I know exactly, what I'm supposed to think about it. This is normal defensive behavior of religious people. Please, don't use "strawman crap" labelling without reasoning. I can say exactly the same about many posts of yours without problem, because our stances are just dual, not in contradiction.

Do you understand, what the stance duality means? Bellow is the animation of gravitational lensing.

Stance A: You see, this is clear evidence of Lorentz symmetry violation in vacuum! Everybody can see, the light is moving more slowly through vacuum near massive object..

Stance B: Nope you troll. Everybody can see, the light speed remains exactly the same along whole path of photon motion. The photon is just moving along longer path in curved space-time near massive object.

Now try to decide, which stance remains more correct, by now? In general, the "local" perspective, which fits the existing observations better is usually less suitable for general predictions and vice-versa. But this is everything, what we can say about their validity in general.

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This simply means, we would never be able to measure the mass of photon directly. Which effectivelly means, when weighting some photon, we will be always forced to weight some other system (like the photon resonator), as you pointed out correctly above. And I've nothing against such stance.

But the fact, we cannot never measure the photon mass directly effectivelly means, you cannot never prove, the photon has no rest mass at the same time. Therefore your argument can be interpreted by symmetric way.

The true is, the formally thinking people have trouble with concept of mass of photon, because it will make their simple equations singular. But this is just a problem of formal math, not the reality, which gets into singularities quite often.

You don't get to redefine terms to suit you, which is basically what you're trying to do here. For the photon to behave as it does, from relativity, its rest mass must be zero. If it were not, there would be ramifications that can be measured. These put an upper experimental bound on the value, and it's consistent with zero.

If you have another formalism that works with a massive photon, publish it. But when in the physics section, we use established physics as the basis for our discussions.

I'm just describing exactly, what I can see. No less, no more. And this is not about some conspiracy at all. The people like you are speaking for himself by the same way, like me. Neverthelles, the intersubjective thinking affects the thinking of individuals by tangible way - the human society is a sort of colony, a metarorganism. The community stance affects the behavior of individuals subconsciously.

At the moment, you cannot justify your stance, or even delete my posts without reasoning, I know exactly, what I'm supposed to think about it. This is normal defensive behavior of religious people. Please, don't use "strawman crap" labelling without reasoning. I can say exactly the same about many posts of yours without problem, because our stances are just dual, not in contradiction.

It is strawman crap when you make the claim that science is a religion, and use that to attack arguments. Standard physics is the baseline. If you think it's wrong, then you have to present valid arguments and empirical data. I don't have to justify my stance on equations and derivations that are easily obtained on the web or in physics textbooks.

Another example, where the photons are manifesting their mass is so called materialization of radiation. During this the pair of photons interacts mutually under formation of new massive particles. We can interpret such process easily as a result non-ellastic Compton collision of photon pair, during which their mass remains at place.

One photon, not a pair.

By my opinion, the pair production violates even the zero rest mass of photon assumption, as the particles without rest mass (i.e. those fulfilling the Bose-Einstein statistics) can never interract mutually.

That will come as a surprise to people doing Bose-Einstein Condensation, who depend on Bosons to interact.

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..If you have another formalism that works with a massive photon, publish it. But when in the physics section, we use established physics as the basis for our discussions..

I already linked a few publications of peer-reviewed experiments, which are using massive photon concept, but you have ignored them completely without reading. The problem is, you're applying biased criterions of what "established physics" is and what's not. For example, the string theory is using many such formalism, i.e. tachyons, Lorentz symmetry violation (which is tightly related to massive photon concept, by the way), etc. and it's allowed to talk about it here. But the string theory wasn't proved yet experimentally by the same way, like the massive photon.

:confused:

By such way, many people tends to believe in some theory, just because of massive propaganda in media, while other theories/concepts are ignored, even if they're of same relevancy or even proposing the same concepts by more intuitive ways. I don't like such approach, because it makes the physics biased and religious gradually. My only criterion of truth is logic, as simple logic, as possible by Occam's razor criterion.

If you'll use such approach, you cannot fall into belief and to use a biased criterions.

..people doing Bose-Einstein Condensation, who depend on Bosons to interact..

Nope, the bosons in BE condensate aren't supposed to interact mutually, from this superfluidity and superconductivity arises. These bosons are formed by interaction of fermions instead, for example by Cooper pair production. We can see this as low energy analogy of photon production by pairing of fermions and anti-fermions.

But you're right at the point, whenever some distinct particle exists. it behaves like fermion as well. Just because of finite curvature of space-time, which is forming such particle. Therefore is some boson exists as a distinct particle, it violates the Lorentz symmetry less or more later. Therefore every rule in the nature is of limited scope, even the sufficiently small photons can create another fermions during materialization of radiation,

We can say, every fermions can create bosons and these bosons can create another generation of fermions under sufficiently low/high energy density conditions, from this the gauge group theory arises. As I explained previously, the gauge symmetry group, for example the Lie E8 group can be interpreted as a tight structure of particles and intercalated gauge bosons and gauge bosons formed by mutual interactions of these bosons recursively like the nested structure of kissing hyper spheres, sitting at the kissing points of another hyper-spheres. From this structure the Lizzi Garret theory arises, by the way.

..One photon, not a pair..

Nope, the pair production always requires pair of particles in its beginning, not just the single one. I already linked Feynman diagram of it above.

Can you explain, why is it so? The Aether theory can. I'm here just for explanation of existing physics by way, which everybody can understand, not for promotion of some private theory. The Aether theory is not mine, it's very old one and I'm totally independent on it, in fact. I can use whatever else theory in my explanations, because I know mainstream physics well, but these theories aren't simple, consistent the less. They were designed to compute particular aspects of reality by schematic way, not to explain them. While I appreciate such approach in quantitative predictions, such formal theories cannot serve as an effective tool for consistent understanding of reality, but the thorough description of it. This is not the very same job: you can combine the equations for years, but you'll never understand the connections behind it.

I'm just here to demonstrate, the contemporary understanding is biased, because the mainstream science is looking for MOST EXACT description of reality systematically, not for MOST SIMPLE one. Unfortunately, such approach violates the Occam's razor criterion or even causality logic in its consequences, because we cannot have an exact and simple description of reality at the same moment - these criterions are exclusive mutually. We can see the above by pronounced way at the case of string theory, as the most advanced example of "formally exact" approach known so far. Such "exact" approach leads to the landscape of 10E+500 equivalent solutions, i.e. it's becoming as vague, as the most trivial philosophers in its consequences.

If you'll understand this, then you'll understand the motivation of all "crank attempts" to explain reality. These cranks aren't in contradiction with mainstream physics, they're just using a dual strategy. Of course, the most robust and vital strategy is in connection of simplest ideas with most advanced math.

..It is strawman crap when you make the claim that science is a religion, and use that to attack arguments. Standard physics is the baseline..

Believe it or not, the belief is undeniable part of scientific description of reality. Every theory is based on ad-hoced postulates and it's using concepts, which appears the more strange and counterintuitive, the more complex or logical such theory is. The Aether theory is no exception. While the Big Bang theory relies on belief in giant explosion of "nothing", the Aether theory makes such concept more intuitive by introducing of phase transition concept, well known from common situation. But such logical explanation brings and ad-hoced belief in even more incredible amount of matter at its very beginning, then just a single Universe requires. Only God can create such incredible amount of matter, in fact.

We can see, the logic and exactness is always balanced by requirements based on belief. The more exact or logical description we'll develop, the more belief it requires. It's not "it is strawman crap", but the immanent part of our multicomponent reality: you can explain the existence of every object by logical way just under introduction of many smaller objects on the background at the price.

Maybe some clever guy will defy this paradigm by some even more smart approach, but currently I don't see any way, how to avoid the belief in our description of reality. Please note, the more belief, the more distant future we can predict - so we can say, the religious nature of people is a sort of evolutionary adaptation, in fact. For example, it's not so easy to understand, why is it so important not to consume all food supplies before start of winter, but the fast introduced by different religions helps to accept such rule by primitive people.

By such way, even the scientific prejudice against belief and religion in general can become a sort of religion from certain perspective. The Aether theory is based on pluralistic approach consistently, the most stable and atemporal is the system of two balanced paradigms (relativity vs. quantum mechanics) political parties (democrates vs. republicans), etc. due the formation of branes, which are enabling further evolution of more complex structures.

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Just testing something

$$x^{2}$$

Mmmm... the Latex system here is different to what i have been used to

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Just testing something $$x^{2}$$

Use the pictures, instead. The equations doesn't illustrate the ideas, from which they were derived, making the explanation irreproducible and nonscientific by such way...

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Use the pictures, instead. The equations doesn't illustrate the ideas, from which they were derived, making the explanation irreproducible and nonscientific by such way...

I would disagree with you hear, the maths adds far more understanding that just a picture.

Just testing something

$$x^{2}$$

Mmmm... the Latex system here is different to what i have been used to

use [ math ]x^{2}[ /math ] without spaces.

or just click on someone elses equation and you'll get a popup with the code...

$x^{2}$

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...the maths adds far more understanding that just a picture..

Try to describe the trivial fact, the Earth is revolving around the Sun.

Just by using of math.

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Try to describe the trivial fact, the Earth is revolving around the Sun.

Just by using of math.

We've been over this, it can be done. MOVE ON.

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I already linked a few publications of peer-reviewed experiments, which are using massive photon concept, but you have ignored them completely without reading. The problem is, you're applying biased criterions of what "established physics" is and what's not. For example, the string theory is using many such formalism, i.e. tachyons, Lorentz symmetry violation (which is tightly related to massive photon concept, by the way), etc. and it's allowed to talk about it here. But the string theory wasn't proved yet experimentally by the same way, like the massive photon.

:confused:

I count a couple of wiki posts, an arXiv link and an article or two. One abstract on detecting the rest mass of the photon (which does not mean they expect to get a nonzero answer). Where are the peer-reviewed papers using the massive photons?

Nope, the bosons in BE condensate aren't supposed to interact mutually, from this superfluidity and superconductivity arises. These bosons are formed by interaction of fermions instead, for example by Cooper pair production. We can see this as low energy analogy of photon production by pairing of fermions and anti-fermions.

The bosons in BEC are already Bosons, i.e. before the experiment starts, unlike Cooper pairs which are Bosonic Couplings of Fermions that form in a transition. It's the interactions that allow the BEC to form, and why it's much more difficult to form the Fermionic analogue, a Fermi degenerate gas. Perhaps I don't understand what you mean by "interact mutually"

Nope, the pair production always requires pair of particles in its beginning, not just the single one. I already linked Feynman diagram of it above.

Look at your link. There's a picture. It has one photon in it, not two.

The nucleus is necessary because you can't conserve momentum in $\gamma \rightarrow e^-e^+$ without it.

I'm just here to demonstrate, the contemporary understanding is biased, because the mainstream science is looking for MOST EXACT description of reality systematically, not for MOST SIMPLE one. Unfortunately, such approach violates the Occam's razor criterion or even causality logic in its consequences, because we cannot have an exact and simple description of reality at the same moment - these criterions are exclusive mutually. We can see the above by pronounced way at the case of string theory, as the most advanced example of "formally exact" approach known so far. Such "exact" approach leads to the landscape of 10E+500 equivalent solutions, i.e. it's becoming as vague, as the most trivial philosophers in its consequences.

Simple isn't acceptable if it doesn't give the right answer.

If you'll understand this, then you'll understand the motivation of all "crank attempts" to explain reality. These cranks aren't in contradiction with mainstream physics, they're just using a dual strategy. Of course, the most robust and vital strategy is in connection of simplest ideas with most advanced math.

That's the problem with cranks though. They aren't interested in the same things as mainstream science, and think that it's science's fault. Science is about explaining how nature behaves, but not necessarily why it behaves that way. You want the metaphysics department, two buildings down. Cranks seems to have this ingrained fear of making a specific, testable prediction, without which one simply cannot demonstrate whether the explanation is wrong, and being verifiably wrong is the goal. That way we can keep eliminating crap, and whatever is leftover is worth something.

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If a photon had mass would not the speed of light have already obliterated the earth? That would make our sun one mean machine right?

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If a photon had mass would not the speed of light have already obliterated the earth? That would make our sun one mean machine right?

The answer is probably "no". I don't know what you mean but you possibly meant that if photons had mass the energy of the photons coming from the sun would be significantly larger. It'd be the same.

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The answer is probably "no". I don't know what you mean but you possibly meant that if photons had mass the energy of the photons coming from the sun would be significantly larger. It'd be the same.

Right but if I throw a gram of mass at you not saying mass is the same as weight it be a bit different then if it came at you at say the speed of light, so if a photon has mass, it then cant have any weight, or turning on a light bulb would be very difficult right?

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Still not sure where you're going with this. Photons have momentum.

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Mass is all to do with how difficult it is to change the speed of something. You know, F=ma. Photons travel at c. You can't change the speed of a photon to c+x or c-x. That's why mass doesn't apply to a photon.

But put that photon in the box bouncing back and forth, and the box has more mass. Because there's more energy in the box, because E=mc², and because you can move the box. It's to do with the symmetry between momentum and inertia.

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F= dp/dt

And again

You want E2 = (mc2)2 + p2c2

NOT

E = mc2

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Wrong. There is no mass term in F= dp/dt. The mass of an object is to do with how difficult it is to change its speed. That's why the photon has no mass. You can't change its speed. Because if you do, it isn't a photon any more. Did you even read what I said yesterday? When you look at E²=p²c² + (mc²)² and think about the electron prior to annihilation, imagine it's not moving, whereupon it has no momentum, so E²=(mc²)². After annihilation the electron has been converted into a 511KeV photon moving at c, and a photon has no mass but it does have energy/momentum E=hf or p=hf/c, so by conservation E²=p²c². Note that what we've basically got here is E² = (mc²)² = p²c², and that demonstrates the relationship between momentum and inertial mass. In essence momentum and inertia are the same thing. It depends on who you say is moving.

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Wrong. There is no mass term in F= dp/dt.

Yes there is.

The mass of an object is to do with how difficult it is to change its speed. That's why the photon has no mass. You can't change its speed. Because if you do, it isn't a photon any more.

Nope.

Did you even read what I said yesterday?

Yes.

When you look at E²=p²c² + (mc²)² and think about the electron prior to annihilation, imagine it's not moving, whereupon it has no momentum, so E²=(mc²)². After annihilation the electron has been converted into a 511KeV photon moving at c, and a photon has no mass but it does have energy/momentum E=hf or p=hf/c, so by conservation E²=p²c². Note that what we've basically got here is E² = (mc²)² = p²c², and that demonstrates the relationship between momentum and inertial mass. In essence momentum and inertia are the same thing. It depends on who you say is moving.

Nope, wrong.

Keep it up, the more you post, the closer I get to bingo .

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Yes there is.

Not for a photon, though. I think it needs to be made clear when a statement is intended to be generally true or specifically for a photon.

But put that photon in the box bouncing back and forth, and the box has more mass. Because there's more energy in the box, because E=mc², and because you can move the box. It's to do with the symmetry between momentum and inertia.

The box has more mass because there is a photon in it. But not because you can move the box — that's the p^2c^2 term, which is separate from the mass term.

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Not for a photon, though. I think it needs to be made clear when a statement is intended to be generally true or specifically for a photon.

Acknowledged. I was just assuming in general, not for a photon.

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So what happened? Did they found out photon is just energy wave not particle?

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The photon is a particle. The particle of the free electromagnetic field.

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*Technically*, you cannot say a photon is a particle or a wave seperately, but instead saying it is both. This is the wave-particle duality/nature of matter... all matter.

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• 1 month later...

Let's assume that the photon is in a hypothetical massless box that has perfectly reflecting mirrors so that the photon bounces around in the box forever without loss.

My question is this:

Could one accelerate the box-photon system to exactly the speed of light?

montanaembassy

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Let's assume that the photon is in a hypothetical massless box that has perfectly reflecting mirrors so that the photon bounces around in the box forever without loss.

My question is this:

Could one accelerate the box-photon system to exactly the speed of light?

montanaembassy

"Massless box with perfect mirrors" is an unphysical assumption. Once you do that, you really can't draw any valid conclusions.

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